package com.pucong.gitee.database.backup.utils;

import lombok.extern.log4j.Log4j2;

import javax.crypto.*;
import javax.crypto.spec.SecretKeySpec;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Arrays;

/**
 * @author yuan
 * @company gitee.com/pucong
 * @create 2019/10/25 16:30
 */
@Log4j2
public class AESEncryptUtil {

    private final static String password = "autoDatabseManager";

    /**
     * 加密
     * @param content 需要加密的内容
     * @return
     */
    public static String encrypt(String content) {
        try {
            log.info("待加密明文:"+content);
            KeyGenerator kgen = KeyGenerator.getInstance("AES");
            SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG" );
            secureRandom.setSeed(password.getBytes("UTF-8"));
            kgen.init(128, secureRandom);
            SecretKey secretKey = kgen.generateKey();
            byte[] enCodeFormat = secretKey.getEncoded();
            SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
            Cipher cipher = Cipher.getInstance("AES");// 创建密码器
            byte[] byteContent = content.getBytes("utf-8");
            cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
            byte[] result = cipher.doFinal(byteContent);
            log.info("加密后自己日志:" + Arrays.toString(result));
            String contentStr = parseByte2HexStr(result);
            return contentStr; // 加密
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**解密
     * @param contentStr  待解密内容
     * @return
     */
    public static String decrypt(String contentStr) {
        try {
            byte[] content =  parseHexStr2Byte(contentStr);
            log.info("加密后自己日志"+Arrays.toString(content));
            KeyGenerator kgen = KeyGenerator.getInstance("AES");
            SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG" );
            secureRandom.setSeed(password.getBytes("UTF-8"));
            kgen.init(128,secureRandom);
            SecretKey secretKey = kgen.generateKey();
            byte[] enCodeFormat = secretKey.getEncoded();
            SecretKeySpec key = new SecretKeySpec(enCodeFormat, "AES");
            Cipher cipher = Cipher.getInstance("AES");// 创建密码器
            cipher.init(Cipher.DECRYPT_MODE, key);// 初始化
            byte[] result = cipher.doFinal(content);
            return new String(result); // 加密
        } catch (Exception e) {
          log.error("解密错误",e);
        }
        return null;
    }


    /**将二进制转换成16进制
     * @param buf
     * @return
     */
    public static String parseByte2HexStr(byte buf[]) {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < buf.length; i++) {
            String hex = Integer.toHexString(buf[i] & 0xFF);
            if (hex.length() == 1) {
                hex = '0' + hex;
            }
            sb.append(hex.toUpperCase());
        }
        return sb.toString();
    }

    /**将16进制转换为二进制
     * @param hexStr
     * @return
     */
    public static byte[] parseHexStr2Byte(String hexStr) {
        if (hexStr.length() < 1) {
            return null;
        }
        byte[] result = new byte[hexStr.length()/2];
        for (int i = 0;i< hexStr.length()/2; i++) {
            int high = Integer.parseInt(hexStr.substring(i*2, i*2+1), 16);
            int low = Integer.parseInt(hexStr.substring(i*2+1, i*2+2), 16);
            result[i] = (byte) (high * 16 + low);
        }
        return result;
    }

    /**
     * 加密
     *
     * @param content 需要加密的内容
     * @param password  加密密码
     * @return
     */
    public static byte[] encrypt2(String content, String password) {
        try {
            SecretKeySpec key = new SecretKeySpec(password.getBytes(), "AES");
            Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding");
            byte[] byteContent = content.getBytes("utf-8");
            cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
            byte[] result = cipher.doFinal(byteContent);
            return result; // 加密
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        } catch (NoSuchPaddingException e) {
            e.printStackTrace();
        } catch (InvalidKeyException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (IllegalBlockSizeException e) {
            e.printStackTrace();
        } catch (BadPaddingException e) {
            e.printStackTrace();
        }
        return null;
    }

    public static void main(String[] args) {
        String content = "SELECT * \n" +
                "FROM 规划库_财政.j_计划管理_用款计划明细表 AS A \n" +
                "where 预算年度 ='2018' \n" +
                "  AND 行政区划代码 = '123456' \n" +
                "  AND 项目分类代码 = '1'";
        String password = "12345678";
        //加密
        System.out.println("加密前：" + content);
        String encryptResult = encrypt(content);
        System.out.println(encryptResult);

        //解密
        String decryptResult = decrypt(encryptResult);
        System.out.println("解密后：" + decryptResult);


        try {
            File file = new File("D:\\workspace\\qyxm_tl_client-api\\data\\doc\\ceshi1_202009.data");
            InputStream is = new FileInputStream(file);
            int iAvail = is.available();
            byte[] bytes = new byte[iAvail];
            is.read(bytes);
            content = new String(bytes);
            is.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("文件内容:\n" + content);
        //解密
        decryptResult = decrypt(content);
        System.out.println("解密后：" + decryptResult);

    }

}